This invention relates to a balloon catheter. Such a catheter comprises a tubular body having a distal end, a proximal end, and at least two lumens. At the proximal end each lumen is attached to a connector. A balloon has an interior connected to one of the lumens, and is attached to the catheter adjacent the distal end. Thus, a fluid under pressure can be supplied to and removed from the balloon in order to cause the balloon to swell to a greater or lesser degree.
Balloon catheters of this type are generally known, and are used for instance to dilate narrowed blood vessels. For this purpose the catheter is introduced in a patient, and the balloon is positioned in the area of the narrowing. By subsequently supplying fluid under pressure via the connector concerned, the balloon-shaped member will expand, thus pushing the narrowed portion outwards.
With such a treatment, it is essential that the fluid supplied to the balloon is of the right pressure. When there is not enough pressure, dilatation will be insufficient, whereas there will be a danger of trauma when the pressure is too great. The use of such a balloon catheter thus requires great skill on the part of the attending physician.
An object of the invention is to provide a balloon catheter of the type described which can be used to carry out the treatment with a greater chance of success. To this end, the balloon catheter according to the invention comprises a pressure gauge placed in a catheter section leading to the balloon. Such a pressure gauge can be made simple and tractable, hence not impeding the treatment. The pressure gauge will give the performing physician a clear indication of the pressure in the balloon, so that the treatment can be carried out effectively.
As an advantageous embodiment of the balloon catheter according to the invention, the pressure gauge forms part of the connection line to the balloon, providing a very manageable assembly.
In one advantageous embodiment, the pressure acts on opposed piston faces, creating a net reaction force in the direction of the smaller diameter of the opposed piston faces. The force increases proportionally with the pressure. A spring working against the movement of the prison is consequently pushed inwardly, proportional to the pressure, giving an indication of the prevailing pressure.
The piston can be seen directly through the transparent housing, so that this in itself can function directly as an indication member, together with a divided, numerical scale on the housing wall. A magnifying effect can occur at the rounded corners of the housing, allowing more accurate reading.
The invention will be explained in the following description with reference to the attached drawings.